Yerbilimleri, 32 (1), 21–50 Hacettepe Üniversitesi Yerbilimleri Uygulama ve Araştırma Merkezi Bülteni Bulletin of the Earth Sciences Application and Research Centre of Hacettepe University Middle-Late Miocene Spalacidae (Mammalia) From Western Anatolia, and the Phylogeny of the Family Orta-Geç Miyosen Batı Anadolu Spalacidae (Mammalia) Fosillerinin Ailenin Evrimine Katkısı *Şevket ŞEN1, Nuran SARICA2 1CR2P-CNRS, Muséum National d’Histoire Naturelle, 75005 Paris, France. 2İstanbul Teknik Üniversitesi, Maden Fakültesi, Jeoloji Mühendisliği Bölümü, Ayazağa, 34469 İstanbul, Turkey. Geliş (received) : 25 Aralık (December) 2010 Kabul (accepted) : 19 Mart (March) 2011 ABSTRACT The Spalacidae (Rodentia, Mammalia) are among the common elements of Neogene and Quaternary mammali- an faunas in Turkey. Their evolutionary dynamics since the Early Miocene allows their use for dating Neogene and Quaternary terrestrial deposits. This paper describes spalacid fossils from three Middle-Late Miocene localities in Western Anatolia; two of them yielded two new species. To test the monophyly of the known genera and to es- tablish phylogenetic relations of fossil species, a cladistic analysis has been performed. The enlightenment of the- ir evolutionary trend towards adaptation to a fully subterraneous life required the analysis of the dental features of available and well-represented fossil species and the discussion of their phylogenetic relationships. It appears that the first representatives of the family originated in Anatolia during the Early Miocene, as suggested by previo- us studies, then rapidly dispersed into south-eastern Europe, and probably much later (?Pliocene) into southwest Asia and North Africa. Their representatives adapted to a fully subterraneous mode of life during the Late Mioce- ne, when open environments prevailed in western Asia and SE Europe. Key Words: Biostratigraphy, cladistic analysis, Miocene, phylogeny, Rodentia, Spalacidae, systematics, Turkey. ÖZ Köstebekler (Spalacidae (Rodentia, Mammalia) Türkiye’de Neojen ve Kuvaterner yaşlı faunalar içinde sıkça bulunanlardır. Erken Miyosen’den beri gösterdikleri güçlü evrim dinamiği nedeniyle, bu ailenin türleri Neojen ve Kuvaterner karasal tortulların yaşlandırılmasında başarılı olarak kullanılır. Bu yayında Batı Anadolu’da Orta-Geç Miyosen yaşlı üç lokasyonda bulunmuş Spalacidae fosilleri ve onların içerdiği iki yeni tür tanımlandı. Bu aileye katılan cinslerin tek kökenli olup olamadığını ve türler arasındaki evrimsel bağlantıları aramak için kladistik analiz yöntemi kullanıldı. Ailenin evrimsel sürecini ve yeraltı yaşamına uyma nedenlerini daha iyi anlamak amacıyla da bilinen bütün fosil türlerin diş yapıları incelendi. Elde edilen sonuçlar, Spalacidae ailesinin, daha önceki çalışmalarda da belirtildiği Ş.Şen E-mail: [email protected] 22 Yerbilimleri gibi, büyük bir olasılıkla Anadolu’da Oligosenden beri bilinen Cricetidae ailesinden Erken Miyosen veya öncesinde türediğini kanıtlar. Kısa sürede Anadolu çevresindeki bölgelere de ulaşan bu ailenin azami dağılımı Kuvaterner’de gerçekleşir. Köstebeklerin salt yeraltı yaşamına uyuşları büyük olasılıkla Geç Miyosen döneminde açık ortamların Batı Asya ve Güneydoğu Avrupa’da yaygınlaşmasına bağlanabilir. Anahtar Kelimeler: Biyostratigrafi, evrim, kladistik analiz, Miyosen, Rodentia, Spalacidae, Türkiye. INTRODUCTION As mentioned above, the oldest representa- tives of this family are included in the genera The mole rats of the family Spalacidae are Debruijnia and Heramys from the Early Mi- burrowing muroid rodents adapted to subter- ocene. The genus Sinapospalax appeared in raneous life. They have a present day disper- the early Middle Miocene and became extinct sal extending, in the east-west direction, from at the end of the Vallesian (Sarica & Sen, 2003). western Iran to Croatia and, in the north-south Pliospalax is known from the second part of the direction, from Ukraine to northeastern Africa Late Miocene (Turolian) and the Pliocene in the (Topachevski, 1969). The Anatolian peninsula is Balkans and Turkey. The genus Spalax (includ- situated almost central in their present distribu- ing Nannospalax, see below) appeared in the tion territory. The fossil localities of the family Late Pliocene (Topachevski, 1969; de Bruijn, are also situated within its present dispersal 1984). It has to be mentioned here that the ge- area. The earliest representatives of spalacids nus Prospalax Mehely, 1908, known from a few are known from Turkey with Debruijnia arpati Late Miocene – Early Pliocene localities in cen- Ünay, 1996, which first occurs at the locality tral and southeastern Europe, belongs in fact to Keseköy in the Neogene Mammalian (MN) Zone the family Anomalomyidae (Bolliger, 1999). 3, and from Greece with Heramys eviensis Klein Hofmeijer and de Bruijn, 1985, which first oc- Thanks to their relatively rich record in the Bal- curs at Aliveri correlated to MN4 (de Bruijn et al., kans and Anatolia, and also to their evolution- 1992). In the latest Late Miocene, the spalacids ary dynamics, spalacids are a useful biostrati- appear in the northern Balkans, and much later graphic tool for terrestrial Neogene deposits in Israel and NE Africa (Topachevski, 1969; de (Ünay, 1999; Nesin and Nadachowski, 2001; Bruijn, 1984; Tchernov, 1986; Popov, 2004). The Sarıca and Şen, 2003). In addition, their sub- available fossil record seems to suggest that terraneous adaptation is interpreted in terms of the spalacids originated in the Middle East, and climatic changes, which occurred in western more probably in Anatolia. Although Debruijnia Asia and southeastern Europe during the Late clearly has a cricetid-type dentition, the fossil Miocene (Ünay, 1999; Flynn, 2009). record does not allow, for the time being, to root The aims of the present paper are firstly the this family in a particular genus or species of description of new spalacid fossils from three Cricetidae (Ünay, 1999; Sarıca and Şen, 2003). Middle and Late Miocene localities of south- The Miocene and Pliocene fossil record of western Anatolia, and, secondly, the discus- spalacids is quite rich in Turkey, Greece and, to sion of the systematics of the family Spalaci- dae with the aid of a thorough review of fossil some extent, in SE Europe, but sparse in other species and of a cladistic analysis of their den- territories where the family lives today. In Turkey, tal morphology which clears up phylogenetic more than a dozen Miocene and Pliocene lo- relationships between species. The names of calities have yielded spalacid remains referred the genera and species discussed in this paper, to four genera and to eight named species up as well as the localities where they have been today. In Greece, they are known with three found are given in Appendix 1. genera in several Miocene and Pliocene locali- ties. The fossil record is limited, or even absent The new material described in this paper is still elsewhere. under study in the Paleontology Laboratory Şen and Sarıca 23 of the Natural History Museum in Paris. After of these subfamilies. The early history of the its study, it will be stored at the Natural His- Rhizomyinae seems to have taken place on tory Museum of Ankara. The dental terminol- the Indian subcontinent during the Miocene ogy used in this paper is after Sarıca and Şen (Flynn, 1982), that of the Spalacinae in the Mid- (2003). The maximum length and width of each dle East during the Miocene (Ünay, 1996), that tooth were measured using a double axis Mi- of the Anomalomyinae in Central Europe dur- tutoyo measuroscope and are given in millim- ing the Miocene (Bolliger, 1999) and that of the eters. The upper molars are abbreviated as M1, Tachyoryctoidinae in Central Asia during the M2, M3 and lower molars as m1, m2, m3. For Oligo/Miocene”. The great morphological dif- ease of comparison, all specimens were illus- ferences of the oldest representatives of these trated as left; if the original is a right tooth, its taxa and their apparently different evolutionary number on the figure is underlined. history led most paleontologists to consider these groups as separate families, issued in- SYSTEMATICS OF SPALACIDAE dependently from early Muroidea sometime in Late Oligocene-Early Miocene. In other words, The status of spalacids as a family or subfamily the fossorial and subterraneous adaptations and their relationships with other rodent families in these groups resulted in the appearance of have been debated since more than a century similar morphological features, which indicate (see Ünay, 1999, and references therein). Cra- an evolutionary convergence rather than a de- nial, postcranial, dental and genetic features of scent from a common ancestor. It is also this spalacids show that they are closely related to opinion that we share, since we consider that Muroidea, among which they form a separate the fossil and extant blind mole rats belong to subfamily (McKenna and Bell, 1997) or a family, an independent family, the Spalacidae. the Spalacidae Gray, 1821 (Musser and Carle- As noted above, the oldest record of this fam- ton, 2005). According to Musser and Carleton ily is Debruijnia arpati Ünay, 1996 from the Ear- (2005: 907), this family contains all extant “spe- ly Miocene (MN 3 zone) of Keseköy in Turkey. cies of fossorial and subterraneous muroids ar- Several other Early Miocene localities in Turkey ranged in the Myospalacinae (zokors, Eospalax also yielded Debruijnia arpati or Debruijnia sp. and Myospalax), Rhizomyinae (bamboo rats (Sabuncubeli, Söke, Dededağ, Gördes-Kınık Cannomys and Rhizomys),